Due to increasingly stringent regulatory requirements more and more electronic devices contain devices which optimize the supply current consumed in terms of the harmonics contained therein. Conventionally designed switching power supplies usually have a rectifier and a smoothing capacitor. The latter is only charged under load when the instantaneous value of the sinusoidal supply voltage rises above the DC potential of the smoothing capacitor. The consequence is only a short current pulse, which recharges the capacitor. A Fourier analysis of this current waveform usually shows numerous harmonics. Depending on the relevant standard, this may make approval or certification more difficult or even impossible.
It is known from patent DE 10 2010 063 126 A1 that in order to charge the high-voltage vehicle battery of a hybrid or electric vehicle via, for example, a public mains power supply, a charging device is required. Known charging devices for high-voltage vehicle batteries usually consist of a rectifier with line filter, a power factor correction circuit as well as a potential separation device.